RE:RE:Vern Yu LetterCurvature: You have to know engineering design to determine whether this is a safety issue or a t legal/political issue. When this line was built 50 yrs ago, engineering methods and precision was less than now. To compensate for this, significant saftey/conservative designs were implimented. If curvature is the issue, then I would expect it to be well within safety limits and meet all engineering standards. This is why no leaks have occured and history carries a lot of weight. If curvature is the issue then Bechtel is liable as they are they are experts not ENB. Now days our designs are much tighter and do not have the margins of old.